Part:BBa_K317000

Halobacteria exhibit phototaxis responses to changes in light intensity and color using the seven-transmembrane retinylidene photoreceptors sensory rhodopsins II (SRII).Light-activated SRII transmits signals to their cognate transducer, HtrII, respectively. The Htr protein contains two transmembrane helices and cytoplasmic methyl-accepting and His-kinase-activating domains homologous to those of chemotaxis transducers of eubacteria,such as the Escherichia coli and Salmonella enterica serovar
Typhimurium Tar, chemotaxis transducer for serine and aspartate, respectively. Sensory rhodopsin
II from Natronobacterium pharaonis (NpSRII) is very similar in spectroscopic and functional properties to the repellent receptor SRII in Halobacterium salinarum. And it has been found to be more stable in response to variation in external conditions such as pH and ionic strength. The NpSRII protein mediates
a repellent response to blue-green light (497 nm) when it is coexpressed with its transducer, NpHtrII, in H. salinarum. Also, when expressed in E. coli, NpSRII is capable of binding all-trans retinal to form a blue-green-lightabsorbing pigment.

We confirmed that phototaxis device (BBa_K317028) properly works as we expected. This result shows that this part will be work after the construction of chimeric fusion protein by using BBa_K317001,BBa_K317002. When you want to check the function of chimeric fusion protein, you should combine the series of promotors and ribosome binding sites with the upstream of the chimeric fusion protein.